Metallic pigments masterbatches

When extruding PVC, it is often preferred to meter the masterbatches or monobatches of the metallic pigment directly into the extruder. 

Other metallic pigments are coated with inorganic (mostly siUca) or organic (polymer) materials to improve their chemical and thermal stabiUty in waterborne coatings, powder coatings, masterbatches, non-conductive coatings etc. 

If fire retardant additives are being used based on halogens, they also can react with metallic pigments. To avoid a chemical reaction, either the encapsulated aluminum or the encapsulated bronze pigment is recommended. Also it is possible to add the metallic pigment as a masterbatch, thereby avoiding direct contact and a chemical reaction between the metal and the halogens. 

Metallic pigments, especially for automobile applications such as bumpers, door panels, grips, buttons, hub covers, and scooter panels and wings, are a focal point of current development by Clariant Masterbatches Division. The company also claims it has the first colour masterbatch series for HDPE packaging with an anodized aluminium appearance, giving high reflectivity, chrome, and lustre. 

To optimize the metallic effect when using an injection-molding machine, a higher screw speed, a longer plasticising period, sufficient backpressure, and a suitable screw design are prerequisites. The pigments are added as ready-to-use compounds, masterbatches, or powders. 

To optimize the metallic effect, the conditions outlined in Section 14.4.4 under Injection Molding should be maintained. The pigments are added as compound, masterbatch, or powder. The use of static mixers or special mixing screws can improve the homogeneity of the blend. For the pinch tube process the high melt viscosity should be considered when preparing the masterbatch. 

The main applications of metallic effect pigments are paints and coatings, printing inks and graphic arts as well as plastics and colorants (masterbatches). 

Pigments Dust contamination of products and workplace, escape to outside possible dust explosion heavy metals (cadmium) Use formulated systems, liquids or masterbatch where powder is essential, ensure good packaging, if possible use a dedicated area ventilate cadmium being phased out... 

Left Colour streaks due to an incompatible masterbatch Right Orientation of metal-effect pigments caused by the flow... 

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